1. Technical Field
The present invention relates to an improvement in a connecting device for a flat circuit device to be used for automobiles and industrial machines.
2. Related Art
In recent years, various electrical apparatuses developed by a technique for enhancing the functions of vehicles have tended to be employed and mounted on automobile as represented by a navigation system and an air bag system, and have been demanded increasingly. Correspondingly, the number of wire harnesses provided in a body is increased. From the point of view of workability and effective utilization of an interior space, a so-called flat circuit 1, which is formed by converging and burying a conductor or conductive material 2 with an insulating resin and is elongated and flat, has been implemented as shown in FIG. 14.
The flat circuit 1 is provided, in some middle portions, with an exposure window 4 for extracting a current of a power supply, such as a battery of an automobile, such that a current can be supplied from proper portions, and is thus provided in a component of an instrument panel, for example. However, the number of the conductors or conductive materials to be provided is increased through an enhancement of the functions of the vehicle as described above. For this reason, the flat circuit 1 is correspondingly used by stacking a layer (two layers, in this case) through an adhesive or fastening means 3.
In a conventional apparatus, as shown in FIG. 14, in the case that an end of the flat circuit 1 is cut and a supply current is taken out therefrom, another conductor or conducting material 5 is electrically connected to the conductor or conductive material 2 facing the exposure window 4 on the end side and a metal terminal (not shown) attached to the end of the conductor or conductive material 5 is inserted in and connected to one of sides of a connector housing 6. A metal terminal (not shown) on a harness end for various apparatuses such as a wiper motor, traveling instruments or an audio system is connected to the other side of the connector housing 6.
In the conventional device, an electric wire 2 of each layer is connected through the conductive material 5. Therefore, there is a high possibility that the conductive materials 5 might come in contact with each other before reaching the connector housing 6. Furthermore, the metal terminal on the conductive material 5 side comes in contact with that of the harness on the electrical device side in two portions of the connector housing 6. Thus, the number of the contact portions is increased correspondingly so that connecting reliability might be deteriorated.
Since each flat circuit 1 has such a structure that layers are provided without a clearance with an adhesive, the conductor or conductive material cannot be connected from the conductor or conductive material facing the exposure window in the middle of the lower flat circuit. Moreover, if the conductor or conductive material is to be electrically connected from the lower flat circuit, it is connected at the end of the flat circuit as shown in FIG. 14. The conductors or conductive materials 2 for the layers are connected to each other by using the conductors or conductive materials 5. Therefore, there is a high possibility that the conductors or conductive materials 5 might come in contact with each other before they reach the connector housing 6. Moreover, there are three nodes in total between the conductor or conductive material 2 and the conductor or conductive material 5 in the flat circuit and between the conductor or conductive material and the metal terminal and between the metal terminal and a metal terminal of a harness on the electrical device side in the connector housing 6. Thus, the number of the contacts is increased correspondingly. Consequently, connecting reliability might be deteriorated.
The invention has been devised in consideration of the circumstances and has an object to obtain a flat circuit device capable of supplying a supply current from a multilayered flat circuit with connecting reliability maintained.
In order to solve the problem, according to the present invention, there is provided a flat circuit device in which a connector is fitted and connected, in an almost vertical direction, into a flat-shaped flat circuit in which a conductive material is wired in parallel and is buried with an insulating material, the flat circuit has at least two layers provided thereon, a step is formed on an end of the flat circuit having two or more layers, an exposure window is provided on the flat circuit in the vicinity of the step and the conductive material is exposed to an outside, and a metal terminal of the connector is electrically connected to the conductive material exposed to an inside of the exposure window through the fitting of the connector.
In the flat circuit device of the present invention, the connector is formed such that a plurality of metal terminals are accommodated in a connector housing thereof and an end of the metal terminal has a length varied corresponding to the step.
In the flat circuit device of the present invention, the connector housing is formed such that an end face opposed to the step of the flat circuit is step-shaped corresponding to the step.
In the flat circuit device of the present invention, the metal terminal of the connector housing has an end formed elastically deformably and the metal terminal elastically comes in contact with the conductive material exposed to the inside of the exposure window against spring force of the metal end during the fitting of the connector.
In the flat circuit device of the present invention, the end of the metal terminal of the connector housing is welded and connected to the conductive material exposed to the inside of the exposure window.
In the flat circuit device of the present invention, the connector is constituted such that the connector housing is divided corresponding to the flat circuit and the connector housing corresponding to the step is integrated to be fitted and bonded into the flat circuit.
According to the invention, the flat circuit has at least two layers provided thereon, a step is formed on an end of the flat circuit having two or more layers, an exposure window is provided on the flat circuit in the vicinity of the step and the conductive material is exposed to an outside, and a metal terminal of the connector is electrically connected to the conductive material exposed to an inside of the exposure window through the fitting of the connector. Therefore, the number of electric nodes is decreased and the conductive material is directly connected from the lower layers of a multilayered circuit.
According to the invention, the connector is formed such that a plurality of metal terminals are accommodated in the housing thereof and an end of the metal terminal has a length varied corresponding to the step. Therefore, it is possible to easily attach the connector to a portion where the terminal of the multilayered flat circuit is stepped.
According to the invention, the connector housing is formed such that an end face opposed to the step of the flat circuit is step-shaped corresponding to the step. Therefore, the connector can be stably fitted in the multilayered flat circuit.
According to the invention, the metal terminal elastically comes in contact with the conductive material exposed to the inside of the exposure window against spring force of the metal terminal during the fitting of the connector. Consequently, electric connection can be carried out reliably.
According to the invention, the end of the metal terminal of the connector housing is welded and connected to the conductive material exposed to the inside of the exposure window. Consequently, reliable electric connection can be obtained.
According to the invention, the connector is constituted such that predetermined connector housings are integrated with each other and fitted in the flat circuit corresponding to the number of the stacked layers of the flat circuit.
The present invention has been devised in consideration of the circumstances and has an object to obtain a connecting device for a flat circuit capable of branching a circuit in the middle of the multilayered flat circuit.
In order to solve the problem, according to the present invention, there is provided a flat circuit device in which an exposure window for exposing a conductor or conductive material is formed on a flat-shaped flat circuit having the conductor or conducting material wired in parallel and buried with an insulating material, a connector housing accommodating a terminal capable of being directly connected is attached to the conductor or conductive material exposed through the exposure window, the flat circuit is multilayered to have two or more layers and a terminal of the connector housing is individually connected to the conductor or conductive material exposed through the exposure window formed for each layer of the flat circuit, and the flat circuit of each layer having the connector housing attached thereto is further integrated by a connecting mechanism.
In the flat circuit device of the present invention, the connector housing is protruded outward from a side surface of the flat circuit and is provided such that a fitting portion on the other side capable of being connected to a circuit on the other side is exposed to a protruded end.
In the flat circuit device of the present invention, the connecting mechanism is formed by an engagement projection provided on the flat circuit and an engagement hole to be fitted therein, and adjacent flat circuits are bonded through fitting of the engagement projection in the engagement hole.
In the flat circuit device of the present invention, the connecting mechanism is formed by a locking portion provided in the connector housing and a locked portion to be fitted therein, and the adjacent connector housings are bonded to each other through fitting of the locking portion in the locked portion.
In the flat circuit device of the present invention, the protruded end of the connector housing is set to be placed in such a position that it is bent at a predetermined angle with respect to a flat face of the flat circuit.
According to the invention, the flat circuit is multilayered to have two or more layers and a terminal of the connector housing is individually connected to the conductor or conductive material exposed through the exposure window formed for each layer of the flat circuit, and the flat circuit of each layer having the connector housing attached thereto is further integrated by a connecting mechanism. Therefore, an electric circuit can be taken out from the middle portion of the lower flat circuit.
According to the invention, the connector housing is protruded outward from a side surface of the flat circuit and a fitting portion on the other side capable of being connected to a circuit on the other side is exposed to a protruded end. Therefore, other circuits and auxiliary machines can easily be fitted without the disturbance of the flat circuit.
According to the invention, the connecting mechanism is provided on the flat circuit. Therefore, the flat circuits are integrated, connecting reliability is enhanced and the whole connecting device is made small-sized.
According to the invention, the connecting mechanism is also provided in the connector housing. Therefore, the flat circuit and the connector housing are wholly integrated strongly.
According to the invention, the protruded end of the connector housing is inclined with respect to the flat face of the flat circuit. Therefore, a connector housing having the best inclination is selected for use depending on the position and direction in which the circuit on the other side is to be attached.